High-Pressure Fuel Pump Troubleshooting

[CorkSport]

Anyone who’s anyone in the Mazdaspeed community will always recommend a high-pressure fuel pump internal upgrade before you start to go crazy down the mod list. Why?

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[nybe0010]

cuz if you don't your gonna have a bad time

[Boucher12]

Great read. Thanks for putting this together.

[Insiatent]

I already have a cobb intake, everything else stock, would adding a ots tune being too much for stock hpfp?

[MRR]

Originally Posted by Insiatent I already have a cobb intake, everything else stock, would adding a ots tune being too much for stock hpfp?

IMO, install an upgrade HPFP, that way, it gives you peace of mind knowing the fuel supply is more than sufficient. Its the very first mod I've done....

[CorkSport Vincent]

Originally Posted by Insiatent I already have a cobb intake, everything else stock, would adding a ots tune being too much for stock hpfp?

No, in a nuthsell there is never a bad time for a tune. We can always use a tune to extract the most performance and reliability out of any modification we have on the car.

[sharksinspace]

Originally Posted by Insiatent I already have a cobb intake, everything else stock, would adding a ots tune being too much for stock hpfp?

A lot of people will tell you that it depends on which gen speed you have. With first gen, you can get away with a couple of more mods before HPFP becomes vital; with second gen, many guys say that HPFP is required for just an upgraded intake.

[Insiatent]

Alright thanks

[Insiatent]

I have gen 2, however i have a bluetooth dongle, and torque app with mazdaspeed addon, made bunch of test and never gone under 1600 psi

[Gerbilo]

I have a CS SRI and TIP on a Pu. Ran that way for a long time, nothing to monitor. Never had any problems, but in retrospect, better to be safe than sorry. Got an AP, loaded the Cobb OTS "Stage 0" tune, logged a few times in different conditions, and didn't see the fuel pressure drop. Loaded the "Stage 1", which is, according to Cobb, safe for stock HPFP, and saw pressure drop on my first log. Not much, but below 1600psi for multiple cells, and that was it for me. Went back to the Stage 0 and installed my internals immediately. Now, I don't even have to worry about it and can add more without any issues.

So, if you want to run safe, without worries, on a Cobb OTS, get the most out of a real tune/OTS+/etc. from a tuner, or add any more power mods, just get the HPFP internals done now so you are in the clear. They are a lot cheaper than a new block.

People may tell you otherwise, but this made sense for me.

[Bingo]

The way I see it is that if you're going to mod any more in the future thereby undoubtedly requiring a HPFP, why not just do it now instead of toying with the devil? If it comes down to not being able to spend $300 on your car right now, then modding should not be the path you take.

[Insiatent]

Yes, i am aware that hpfp upgrade is a no-choice for modding, but i dont think i would go any higher than a ots tune and my cobb sri this year, if i could avoid being forced to get a hpfp untill i want to add a tip or dp, it will be ideal, from what ive heard, some genpu will keep higher pressure than other.

I should also check if my hpfp could already be modded, i got my genpu at 63k km, already had a cobb rmm when i got it.

[sharksinspace]

Genpus are a riskier venture when it comes to HPFP, from what I've read; like you said, not all genpus are equal and while some will be fine with light modding on stock internals, others have had issues after just an intake. The dangerous part is that when the pump goes bad, it tends to do so without warning and happens quickly enough that live monitoring won't be able to save you.

If you can spare the money, it really is worth it just for peace of mind; it's not as tough of an install as it may seem and is great insurance...$300 for beefier internals is better than the cost of a new engine, after all.

[Insiatent]

What are the symptoms of a hpfp going bad? Or at least not pushing enough?

[sharksinspace]

My understanding is (someone more knowledgeable please chime in if I'm incorrect or missing info):

1. Internals get overloading and can't keep up with fuel demand, pressure drops
2. AFR leans out due to dropped pressure
3. ECU tries to compensate for lean condition by pushing more fuel
4. Additional fuel overloads internals even more
5. Cycle repeats itself until Zoom Zoom Boom

There's really no forewarning or pre-failure symptoms that you can look for that will tell you it's about to go bad, unless you happen to catch sign of pressure dips through datalogging (in which case drive it easy until internals are upgraded); it's just good until it's very bad.

[Insiatent]

Okay i understand, but more scientist, its a huge detonation that happen at this moment?

[sharksinspace]

Typical outcome is that you end up with a new (and unwanted, obviously ) hole in your block. Not trying to put the fear in you or anything, I just know how much I would hate to ZZB my MS3 and therefore don't like seeing it happen to anyone else.

[Insiatent]

Yeah me neither.
I could try stage 0 tune first, if its still stay plenty higher than 1600, then i could try stage 1, if stage 0 is not trusty, then i go back stock untill hpfp upgrade.

[Insiatent]

So today i tried to check the hpfp, when i removed the battery, there was weird green fungus and bolt was all eaten, dunno if previous owner had a battery leak or something but now i cant manage to remove the damn battery case bolt, completly ceased and no box size fit properly, tried with vise grip but was too hard and rounded bolt.

Shit